Physics News

Latest physics and nanotechnology news headlines

Quantum dots brighten the future of lighting

Nanotechnology is often confined to niche products, but quantum dots are so versatile they could be used in everything from light bulbs to laptopsThe properties of a material were once thought to be defined only by its chemical composition. But size matters too, especially for semiconductors. Make crystals of silicon small enough - less than 10 nanometres - and their tiny dimensions can start to dictate how the atoms behave and react in the presence of other things. These tiny bits of semiconductor crystals - so-called quantum dots - have such remarkable, novel properties that scientists think they will soon be used in everything from light bulbs to imaging of cancer cells or in the design of ultra-efficient solar cells.Semiconductors such as silicon or indium arsenide are chosen to build electronic circuits because of the discrete energy levels at which they can give off electrons or photons. This makes them useful in building switches, transistors and other devices. It was once thought these energy levels -